Proposal of a Novel Pole Type Structures in Perpendicular MRAM for High Gb/Chip

This paper proposes a novel MRAM using perpendicular magnetic tunnel junction device for high capacity. Conventional MRAM has weak points to realize high capacity in the design structure of the cell, one of which is that using simple current injection system can generate only weak switching field. As a solution, we propose a novel MRAM that has two additional poles in this paper. Proposed novel MRAM has a strong switching field owing to two poles added on both sides of the free layer, just like perpendicular magnetic recording heads. In this paper, analysis of the switching field and useful designs for high Gb/Chip are presented. This research was done using three dimensional FEM with injected current density of 8 times 10⁷ A/cm² -6 times 10⁸ A/cm².